Showing papers in "Radiology in 1986"
TL;DR: A magnetic resonance (MR) method to image intravoxel incoherent motions (IVIMs) by using appropriate gradient pulses and nonuniform slow flow of cerebrospinal fluid appeared as a useful feature on IVIM images.
Abstract: Molecular diffusion and microcirculation in the capillary network result in a distribution of phases in a single voxel in the presence of magnetic field gradients. This distribution produces a spin-echo attenuation. The authors have developed a magnetic resonance (MR) method to image such intravoxel incoherent motions (IVIMs) by using appropriate gradient pulses. Images were generated at 0.5 T in a high-resolution, multisection mode. Diffusion coefficients measured on images of water and acetone phantoms were consistent with published values. Images obtained in the neurologic area from healthy subjects and patients were analyzed in terms of an apparent diffusion coefficient (ADC) incorporating the effect of all IVIMs. Differences were found between various normal and pathologic tissues. The ADC of in vivo water differed from the diffusion coefficient of pure water. Results were assessed in relation to water compartmentation in biologic tissues (restricted diffusion) and tissue perfusion. Nonuniform slow flow of cerebrospinal fluid appeared as a useful feature on IVIM images. Observation of these motions may significantly extend the diagnostic capabilities of MR imaging.
3,679 citations
TL;DR: It is imperative that imaging studies be performed with great care, diagnoses be based on rigid criteria, and that more experience with difficult lesions be gained so that the proper approach to treatment will be determined.
Abstract: The radiologic diagnosis of renal cysts (and their differentiation from renal neoplasms) has come a long way since the 1950s when the approach was surgical exploration, unless clinically contraindicated, for every renal mass detected using urography. Nephrotomography, renal angiography, and cyst puncture have contributed over the ensuing years to the differentiation of cyst from tumor. However, for the most part, sonography and CT (or a combination of these when necessary) have become the main diagnostic techniques for evaluating renal masses, and with their use we have never been more accurate, noninvasive, and relatively economically efficient. The more widespread use of CT has enabled serendipitous discovery of many small renal carcinomas, the removal of which should result in an improvement in the overall cure rate of patients with renal parenchymal neoplasms. On the other hand, we are also discovering many more cysts than we have previously. We must be on guard, therefore, against discovering lesions for which we are unable to establish a radiologic diagnosis of benignity, because this will only increase the need for exploratory surgery once again. It is thus imperative that imaging studies be performed with great care, that diagnoses be based on rigid criteria, and that more experience with difficult lesions be gained so that the proper approach to treatment will be determined. If we are able to accomplish this, then the present radiologic age can be remembered as a time when great advances in the evaluation of renal masses were made, with resultant improved patient management and cure of disease.
932 citations
TL;DR: Ultrasound (US) examination during graded compression was performed in 60 consecutive patients with clinical signs of acute appendicitis and the inflamed appendix was visualized in 25 (89%) of 28 patients with confirmed appendix.
Abstract: Ultrasound (US) examination during graded compression was performed in 60 consecutive patients with clinical signs of acute appendicitis. In 25 (89%) of 28 patients with confirmed appendicitis, the inflamed appendix was visualized by US. Perforation was predictable in six of seven patients. In 32 patients without appendicitis, the appendix was not visualized. Graded-compression US is the examination of choice if there is doubt whether an appendectomy should be performed.
724 citations
TL;DR: With this method, suppression of nonmoving spins is essentially complete, yielding a high dynamic range in signal intensity for detected vessels, and not only arterial structures, but also venous structures can easily be visualized.
Abstract: Pulse sequences that permit selective detection of moving spins in a magnetic resonance image have been developed. Experiments were performed by the authors to produce projected angiographic data without the use of contrast agents, with the intensity of each image pixel determined by the macroscopic velocity of the detected spins. With this method, suppression of nonmoving spins is essentially complete, yielding a high dynamic range in signal intensity for detected vessels. Selective detection of moving spins is not dependent on pulsatile flow. Consequently, not only arterial structures, but also venous structures can easily be visualized. High-resolution angiographic images can be obtained by combining the flow experiment with surface coil techniques.
507 citations
TL;DR: In a retrospective analysis of the plain radiographs of 142 cases of pelvic fracture, four patterns of force were identified, presenting distinctive, recognizable radiographic appearances, which correlates with associated injury to soft-tissue structures and enables the surgeon to begin corrective procedures rapidly.
Abstract: Assessment of pelvic fractures in severely traumatized, clinically unstable patients presents a diagnostic problem. Traditional plain-radiographic classifications of the fracture are of limited preoperative value to the surgeon who must apply corrective force in opposition to the original force vector causing the fracture. Computed tomographic scanning is an effective method of examining the pelvis but is time consuming and may be impractical in cases of severe injury. In a retrospective analysis of the plain radiographs of 142 cases of pelvic fracture, four patterns of force were identified, presenting distinctive, recognizable radiographic appearances. These patterns are anteroposterior compression, lateral compression, vertical shear, and a complex pattern. The resulting classification of pelvic fracture, based on radiographic and clinical findings, correlates with associated injury to soft-tissue structures and enables the surgeon to begin corrective procedures rapidly.
471 citations
TL;DR: Percutaneous intratumoral alcohol injection is inexpensive, easy to perform, and potentially valuable in the treatment of selected small neoplastic lesions of the liver and abdomen in patients with inadequate response to conventional treatment or refusal of surgery.
Abstract: Fourteen lesions (nine hepatocellular carcinomas, four hepatic metastases from gastric carcinoma, and one peritoneal metastasis from transitional cell carcinoma) in 12 patients were treated with percutaneous injection of 95% ethyl alcohol under guidance with ultrasound. Requirements for this procedure included inadequate response to conventional treatment or refusal of surgery, easy identification of the tumor with sonography, and a tumor diameter less than 4 cm. Three to nine administrations (75 in all) were performed for each lesion according to its size and to the results of the fine needle biopsy. All lesions had posttreatment sonographic structural changes of fibronecrotic degeneration. All lesions less than 3.2 cm in diameter (11 cases) that underwent the final fine needle biopsy were negative for malignant cells and had volume reductions up to 100%. No biochemical changes or untoward clinical sequelae were detected. Percutaneous intratumoral alcohol injection is inexpensive, easy to perform, and po...
366 citations
TL;DR: Assessment of SPNs by CT is most effective for lesions 2.0 cm or less in diameter, and for larger lesions, the frequency of benign disease was decreased, as was the percentage of benign SPNs correctly assessed as benign by CT.
Abstract: Computed tomography (CT) was used to examine 634 solitary pulmonary nodules (SPNs). Each lesion was assessed as benign or indeterminate on the basis of CT criteria. Benign nodules made up 44% of all SPNs and 58% of the 431 that were 2 cm or less in diameter. All malignant SPNs were assessed as indeterminate, and adenocarcinoma (42%) was the most common primary malignancy. A total of 176 (63% of benign SPNs) were correctly assessed as benign by CT. Ninety SPNs assessed as diffusely calcified were not so identified by conventional tomography at outside institutions. An SPN can be reliably assessed by CT as benign if it exhibits high attenuation values, exceeding a critical level and distributed diffusely throughout a CT section through the center of the lesion and a well-defined edge. Although 38 of 283 (13.4%) primary lung cancers contained localized calcification, there was no significant overlap with the diffuse calcification of benign lesions. Central carcinoid tumors may contain focal ossification, but such lesions may be recognized by noting the proximity of larger bronchi. Assessment of SPNs by CT is most effective for lesions 2.0 cm or less in diameter. For larger lesions, the frequency of benign disease was decreased (14.3% of 203), as was the percentage of benign SPNs correctly assessed as benign by CT (37.9%).
348 citations
TL;DR: It is indicated that because of the poor accuracy of CT in preoperative local staging of colorectal carcinoma, it has virtually no useful clinical role in this regard, however, preoperative CT evaluation of the liver can be useful.
Abstract: CT was performed prior to surgery in 103 patients with colorectal carcinoma to assess its value in staging the tumor. Preoperative IBD scans had sensitivities and specificities of 72.7% and 98.9% in detection of liver metastases, 25.9% and 96% in detection of lymph node metastases, and 61.2% and 80.6% in detection of local extension. Compared with the Duke's classification, CT correctly staged only 47.5% of patients: 16.6% were upstaged, and 83.3% were downstaged. Recurrent tumors developed in 11 of 67 patients followed for more than 24 months. CT depicted recurrence in six patients scanned prior to 12 months. Routine scans obtained at 12 months depicted unsuspected tumor recurrence in three of four patients with proved recurrent disease (one patient with pulmonary metastases did not undergo CT). This study indicates that because of the poor accuracy of CT in preoperative local staging of colorectal carcinoma, it has virtually no useful clinical role in this regard. However, preoperative CT evaluation of ...
300 citations
TL;DR: It is concluded that thin-section CT aided by a reference phantom in equivocal cases should be an integral part of the diagnostic approach to the pulmonary nodule.
Abstract: To evaluate the role of computed tomography (CT) in the investigation of pulmonary nodules, a special reference phantom that enabled CT densitometric measurements independent of variations between scanners and patients was used in ten institutions. A total of 384 nodules not considered calcified by conventional methods were examined; 118 (31%) proved to be benign, and in 65 of these (55%), unsuspected calcification was demonstrated. In 28 of the 65, definite calcification could be identified on thin-section CT scans by simple inspection of the scans at narrow windows. In the remaining 37, presence of calcification could not be clearly established without comparison with the reference CT number from the calibration phantom. CT was most effective in establishing the benignancy of nodules 3 cm or less in diameter and those with discrete or smooth margins. CT rarely yields a confident diagnosis of benign disease in larger nodules and in those with irregular or spiculated borders. After review of prior spot ra...
300 citations
TL;DR: An expandable stainless steel stent was formulated for use in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction and may be effective in overcoming stenosis caused by scarring, extrinsic compression, and collapse of reconstructed tracheo- bronchial structures.
Abstract: An expandable stainless steel stent was formulated for use in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction. The stents were placed through an endotracheal tube into the trachea and bronchi of 11 healthy dogs. The stents expanded over time, substantially increasing the diameter of the lumen. Slight migration occasionally occurred, while an inflammatory reaction was noted in each animal. The stents were successfully used in the treatment of two cancer patients to dilate a postoperative bronchial stenosis that caused pneumonia and to support a tracheal graft that collapsed with respiration. Because of the stent migration in experimental studies, designs are being tested to develop stents with greater stability. These stents may be effective in overcoming stenosis caused by scarring, extrinsic compression, and collapse of reconstructed tracheobronchial structures.
282 citations
TL;DR: Gd-enhanced MR imaging appears to be more sensitive than HICT in the detection of the transient abnormalities of the blood-brain barrier that occur in patients with active MS and appears capable of distinguishing active lesions that may correspond to the anatomic regions responsible for abnormal clinical findings.
Abstract: Magnetic resonance (MR) images--both nonenhanced and enhanced with gadolinium DTPA/dimeglumine (Gd)--were compared with high-iodine (88.1 g I) computed tomographic (HICT) scans in demonstrating lesions in 15 patients known to have multiple sclerosis (MS). T1-weighted, mixed (T1, proton density, and T2), and T2-weighted MR pulse sequences were used. More than 20 lesions in each of 14 patients were demonstrated by pre-Gd mixed images and T2WI. Nine patients had clinical symptoms of active disease. Gd-enhanced T1WI showed at least one lesion that appeared to correspond with newly reported symptoms or signs. In addition, three clinically stable patients showed enhancement. Enhancement was best seen on 3-minute T1WI. HICT scans showed enhancement in four of the nine patients with active disease and in none of five clinically stable patients. Gd-enhanced MR imaging appears to be more sensitive than HICT in the detection of the transient abnormalities of the blood-brain barrier that occur in patients with active MS and appears capable of distinguishing active lesions that may correspond to the anatomic regions responsible for abnormal clinical findings.
TL;DR: Conjugation can be used to synthesize half of the data acquired during a conventional two-dimensional Fourier transform imaging procedure, thus reducing imaging time by nearly half, and in magnetic resonance imaging units in which S/N levels are higher than needed to permit imaging with a single acquisition of each projection.
Abstract: Conjugation can be used to synthesize half of the data acquired during a conventional two-dimensional Fourier transform imaging procedure, thus reducing imaging time by nearly half. The images acquired by this process have the same object contrast and spatial resolution as conventional images do, but with a 40% reduction in the signal-to-noise ratio (S/N). Conjugation can be used to advantage in magnetic resonance imaging units in which S/N levels are higher than needed to permit imaging with a single acquisition of each projection.
TL;DR: The distribution of iron in the brain was analyzed using high field strength magnetic resonance (MR) imaging in 14 healthy control individuals and six patients with Parkinson plus syndromes who were unresponsive to antiparkinsonian therapy.
Abstract: The distribution of iron in the brain was analyzed using high field strength (1.5 T) magnetic resonance (MR) imaging in 14 healthy control individuals and six patients with Parkinson plus syndromes (multisystem atrophy and progressive supranuclear palsy) who were unresponsive to antiparkinsonian therapy. The normal topographic distribution of iron in the brain as indicated by high field MR images coincided precisely with the distribution of iron in the brain as determined by Perls staining for ferric iron. In Parkinson plus syndromes, there were abnormally increased concentrations of iron (decreased T2 relaxation times) in the putamen, and less prominent increases in the caudate nucleus and lateral pars compacta of the substantia nigra. In high field strength MR images of normal patients, the decreased signal intensity in the globus pallidus is more prominent than that of the putamen. In MR images of patients with Parkinson plus syndromes, the decreased signal intensity of the putamen is more prominent than that of the globus pallidus.
TL;DR: In this paper, images of a vascular tree are obtained in a shorter than usual time by deliberately undersampling the object, which results in aliasing, and then processing the undersampled data to eliminate the effects of the aliasing.
Abstract: Images of, e.g., a vascular tree, are obtained in a shorter-than-usual time by deliberately undersampling the object, which results in aliasing, and then processing the undersampled data to eliminate the effects of the aliasing.
TL;DR: It is concluded that MR can depict radiation lesions with great sensitivity but is not very helpful for discrimination between recurrent or residual brain tumor, radiation necrosis, and other brain lesions.
Abstract: This retrospective study was performed to assess the capability of magnetic resonance (MR) to depict and characterize diffuse and focal radiation lesions in the brain using the spin-echo technique. The MR images of 55 patients who had undergone radiation therapy were reviewed. Comparative computed tomography (CT) studies were available for all the patients. Normal white matter was chosen as reference tissue for the quantitative comparison of signal intensities. Radiation lesions (identified in eight patients) were seen as regions of high signal intensity on the sequence with a long repetition time (TR) (2.0 sec) and showed no difference in signal compared with white matter when the TR was short (0.5 sec). Nonspecific prolongation of T1 and T2 relaxation times was measured in such lesions. In one patient, subependymal tumor spread, demonstrated by contrast-enhanced CT, was missed on MR images, masked by the adjacent abnormal signal owing to radiation effects. Recurrent or residual brain tumor could not be distinguished from radiation brain necrosis either by CT or by MR imaging. It is concluded that MR can depict radiation lesions with great sensitivity but is not very helpful for discrimination between recurrent or residual brain tumor, radiation necrosis, and other brain lesions.
TL;DR: A morphologic classification of in utero urinary tract dilatation is presented and it is hoped that use of this simple and practical classification will facilitate communication and comparison of results in the literature.
Abstract: A morphologic classification of in utero urinary tract dilatation is presented. Ninety-two hydronephrotic fetal kidneys diagnosed with ultrasound were graded according to the proposed classification. The findings suggest that grade I dilatation (anteroposterior diameter of the renal pelvis less than 10 mm) should be considered normal. Grades II and III constitute an intermediate hydronephrosis, requiring postnatal urologic surgery in nearly half the cases. Grade IV (moderate dilatation of the calyces, with easily identified residual renal cortex) and grade V (severe dilatation of the calyces with atrophic cortex) are clearly pathologic and require neonatal corrective surgery. It is hoped that use of this simple and practical classification will facilitate communication and comparison of results in the literature.
TL;DR: The interpretation scheme presented here utilizes a systematic structured approach to identify characteristically benign calcifications, for which no further evaluation is needed, and define as suggestive of malignancy those remaining calcifications that present as isolated parenchymal clusters of tiny calcific particles.
Abstract: Breast calcifications may be categorized as benign, probably benign, and suggestive of malignancy. The interpretation scheme presented here utilizes a systematic structured approach: identify characteristically benign calcifications, for which no further evaluation is needed; define as suggestive of malignancy those remaining calcifications that present as isolated parenchymal clusters of tiny calcific particles; and (optional) attempt to downgrade some of these suspicious calcifications into the "probably benign" category, so that they can be managed by periodic mammographic follow-up rather than biopsy. The clinical acceptability of this approach will vary with local conditions; success in implementing it will encourage increased use of mammography, and ultimately, improved breast health care.
TL;DR: To test the ability of Gianturco expandable metallic stents to dilate and maintain patency in stenotic venae cavae, stenosis of the inferior vena cava was created in mongrel dogs by the percutaneous injection of absolute ethanol into the paravascular retroperitoneal space.
Abstract: To test the ability of Gianturco expandable metallic stents to dilate and maintain patency in stenotic venae cavae, stenosis of the inferior vena cava was created in seven mongrel dogs by the percutaneous injection of absolute ethanol into the paravascular retroperitoneal space. Gianturco stents, placed across the stenotic segment, resulted in successful dilatation with improved hemodynamics in four dogs. The stents failed to dilate an occluded vena cava in one dog; in the remaining dogs, stent placement was complicated by early migration and occlusion. Gianturco stents were placed in two patients, one with superior vena cava syndrome and one with retroperitoneal fibrosis that obstructed the inferior vena cava, and resulted in immediate relief of presenting symptoms. These results should be viewed cautiously, but further investigation into the clinical use of the stents is indicated, especially for patients for whom other treatments are difficult.
TL;DR: It is concluded that thin-section CT is an accurate procedure in the recognition of bronchiectasis and lung findings were better visualized on CT scans than on bronchograms.
Abstract: To assess the accuracy of computed tomography (CT) in the evaluation of bronchiectasis, we performed thin-section CT in 36 patients with clinical findings suggestive of this diagnosis. CT was performed with 1.5-mm section thickness and 10-mm intersection spacing. Bilateral (eight patients) and unilateral (28 patients) bronchograms were obtained. CT and bronchographic findings were correlated in 44 lungs. In 15 lungs no bronchiectasis was observed on CT scans and bronchograms. In 25 lungs both examinations accurately indicated the presence and extent of bronchiectasis. In two lungs the extent of disease was underestimated on CT, which failed to indicate bronchiectasis in one segment of the affected lobe. In one case CT findings suggested focal bronchial disease, but the lung was misinterpreted as not bronchiectatic; the bronchogram showed cylindric bronchiectasis. In one case CT disclosed cylindric bronchiectasis in a lobe that was bronchographically normal, but in this case the bronchogram was probably misinterpreted as false negative. In two cases lung findings were better visualized on CT scans than on bronchograms. It is concluded that thin-section CT is an accurate procedure in the recognition of bronchiectasis.
TL;DR: Twelve such cases were proved histologically by means of thoracotomy or needle biopsy; the remainder, including eight in asymptomatic patients aged 65 years or older, were managed with conservative follow-up.
Abstract: Forty-seven patients with a proved (n = 31) or presumed (n = 16) diagnosis of pulmonary hamartoma were studied prospectively by thin-section computed tomography (CT). CT criteria for hamartoma included a diameter of 2.5 cm or less, a smooth edge, and focal collections of fat or fat alternating with areas of calcification. No case of cancer (n = 283) or metastatic disease (n = 72) fulfilled these criteria. Seventeen hamartomas with no detectable calcium or fat were not diagnosed by means of CT. Two other lesions contained diffuse calcium deposits. In 28 lesions, a CT diagnosis of hamartoma was based on the detection of fat (n = 18) or calcium plus fat (n = 10). Twelve such cases were proved histologically by means of thoracotomy or needle biopsy; the remainder, including eight in asymptomatic patients aged 65 years or older, were managed with conservative follow-up.
TL;DR: The signal intensity of the cerebrospinal fluid in the cerebral aqueduct and lateral ventricles on magnetic resonance (MR) images was evaluated in 16 healthy individuals and in 32 patients with various forms of hydrocephalus.
Abstract: The signal intensity of the cerebrospinal fluid (CSF) in the cerebral aqueduct and lateral ventricles on magnetic resonance (MR) images was evaluated in 16 healthy individuals and in 32 patients with various forms of hydrocephalus (20 with chronic normal pressure hydrocephalus [NPH], seven with acute communicating hydrocephalus, and five with hydrocephalus ex vacuo [atrophy]). The low signal intensity frequently observed in the cerebral aqueduct is believed to reflect the pulsatile motion of CSF, which is related to the cardiac cycle. While this "aqueductal flow void phenomenon" can be observed in healthy individuals, it is most pronounced in patients with chronic, communicating NPH; is less evident in patients with acute, communicating hydrocephalus; and is least evident in patients with atrophy. Ventricular compliance is known to be essentially normal in atrophy; mildly decreased in acute, communicating hydrocephalus; and severely decreased in NPH. The degree of aqueductal signal loss is believed to ref...
TL;DR: Real-time ultrasonography (US) using linear-array probes and a stand-off pad as a "waterpath" was performed to evaluate the Achilles tendon in 67 patients believed to have acute or chronic traumatic or inflammatory pathologic conditions, resulting in the diagnosis of focal abnormalities.
Abstract: Real-time ultrasonography (US) using linear-array probes and a stand-off pad as a "waterpath" was performed to evaluate the Achilles tendon in 67 patients (including 24 athletes) believed to have acute or chronic traumatic or inflammatory pathologic conditions. Tendons in 23 patients appeared normal on US scans. The 44 abnormal tendons comprised five complete and four partial ruptures, seven instances of postoperative change, and 28 cases of tendinitis. US depiction of the inner structure of the tendon resulted in the diagnosis of focal abnormalities, including partial ruptures, nodules, and calcifications. Tendinitis was characterized by enlargement and decreased echogenicity of the tendon. The normal US appearance of the Achilles tendon is described.
TL;DR: In patients with a VH and back pain of uncertain origin, the presence of three or more of these signs may indicate a potentially symptomatic VH, and spinal angiography and, in some cases, embolization, are indicated.
Abstract: Radiologic studies of 57 solitary vertebral hemangiomas (VHs) were reviewed to find radiographic and computed tomographic (CT) criteria by which to distinguish asymptomatic lesions from those compressing the spinal cord. Six features were seen significantly more often in those compressing the cord: location between T-3 and T-9, involvement of the entire vertebral body, extension to the neural arch, an expanded cortex with indistinct margins, an irregular honeycomb pattern, and soft-tissue mass. Contrast material-enhanced CT scans and selective spinal angiograms demonstrated extension into the spinal canal. In patients with a VH and back pain of uncertain origin, the presence of three or more of these signs may indicate a potentially symptomatic VH. In such patients, spinal angiography and, in some cases, embolization, are indicated.
TL;DR: Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy and no instance of echogenic cancer was observed.
Abstract: Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed.
TL;DR: Endoscopic retrograde pancreatography (ERP) or operative pancreatography clearly demonstrated characteristic findings: localized, prominent cystic dilatation of a side branch of the main pancreatic duct with grape-like clusters or pear-shaped pools of contrast material associated with filling defects of various sizes.
Abstract: Five cases of localized cystic dilatation of a side branch of the main pancreatic duct due to a new entity ("ductectatic" mucinous cystadenoma and cystadenocarcinoma) are reported. The dilated duct was widely covered by epithelium indistinguishable from that of mucinous cystadenoma (n = 4) or cystadenocarcinoma (n = 1) of the pancreas. All lesions were located in the uncinate process and were about 3 cm in size. On computed tomographic scans and sonograms, lesions were difficult to distinguish from simple cyst of the pancreas unless lobulated or irregular margins were demonstrated. Endoscopic retrograde pancreatography (ERP) or operative pancreatography clearly demonstrated characteristic findings: localized, prominent cystic dilatation of a side branch of the main pancreatic duct with grape-like clusters or pear-shaped pools of contrast material associated with filling defects of various sizes. When a cystic lesion is noted in the uncinate process of the pancreas, ERP is mandatory to confirm or rule out this potentially or overtly malignant disease.
TL;DR: Computed tomography was performed within 10 days of open lung biopsy in nine patients with fibrosing alveolitis and demonstrated patchy involvement of the lung parenchyma, areas with a reticular pattern being intermingled with areas of normal lung.
Abstract: Computed tomography (CT) was performed within 10 days of open lung biopsy in nine patients with fibrosing alveolitis. One-centimeter collimation contiguous scans through the chest were obtained in all patients. Additional 1.5-mm collimation scans were obtained in the area in which lung biopsy was later performed in six patients. In seven patients, CT demonstrated patchy involvement of the lung parenchyma, areas with a reticular pattern being intermingled with areas of normal lung. The reticular pattern was associated with cystic spaces 2-4 mm in diameter and was more severe in the lung periphery. Histologically, the reticular pattern corresponded to areas of irregular fibrosis. One patient had diffuse honeycombing (2-20-mm cysts), and one had honeycombing only in the lung periphery. In all patients, CT clearly defined the architectural changes seen on open lung biopsy. These changes were much better seen on the 1.5-mm than on the 10-mm collimation scans. CT may be helpful in determining the pattern and distribution of lung involvement in patients with fibrosing alveolitis and in guiding the surgeon to the most appropriate area(s) for biopsy.
TL;DR: It is concluded that MR is an accurate modality for imaging uterine leiomyomas, since it clearly demonstrates tumor number, size, location, and the presence and extent of degeneration.
Abstract: Magnetic resonance (MR) imaging, symptoms, and pathologic findings were correlated in 59 uterine leiomyomas from 23 patients. The tumors varied from less than 1 cm to 18 cm in diameter. Fifty-seven leiomyomas were identified in the corpus uterus, one was located within the broad ligament, and another was detected in the cervix. Among the corpus lesions, 9 were correctly identified on MR images as subserosal and 37 as intramural. Of 11 tumors assigned at surgery to the submucosal group, 10 had been accurately defined with MR. On MR, myomas associated with hypermenorrhea produced an anatomic disruption of the "junctional zone" (the low-intensity band seen at the myometrium-endometrium junction on T2 contrast images). Long TR (2 sec) and TE (56 msec) parameters (T2 contrast images) yielded the best contrast resolution between leiomyoma and surrounding myometrium. Correlation of MR with histologic features demonstrated 2 groups of lesions. Leiomyomas free of degenerative changes emitted homogeneous signals of low intensity. Contrast between tumor and myometrium was -16% on the T1 contrast image and increased to -44 +/- 16% on the T2 contrast image. Leiomyomas with hyaline, myxomatous, or fatty degeneration demonstrated various degrees of inhomogeneity, best seen on images obtained with long TR and TE. It is concluded that MR is an accurate modality for imaging uterine leiomyomas, since it clearly demonstrates tumor number, size, location, and the presence and extent of degeneration.
TL;DR: High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions.
Abstract: Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions.
TL;DR: HRCT can demonstrate the location of pathologic changes within a lobule and may be helpful in the differential diagnosis of diffuse pulmonary diseases, and centrilobular emphysema and centrillobular tuberculous nodules can be diagnosed with HRCT.
Abstract: To determine the value of high-resolution computed tomography (HRCT) in the diagnosis of diffuse pulmonary diseases, a direct HRCT-pathologic correlative study was performed using four inflated and fixed lungs from autopsy. In normal lungs, the smallest pulmonary artery resolved by HRCT was 200 microns in diameter; the artery was accompanied by the terminal bronchiole and the first-order respiratory bronchiole. The distance from the vessel to the corresponding lobular border ranged from 3 to 5 mm. These results suggest that the centrilobular area or the area around the terminal or respiratory bronchioles can be recognized with HRCT. In addition, the authors confirmed that centrilobular emphysema and centrilobular tuberculous nodules can be diagnosed with HRCT. Thus, HRCT can demonstrate the location of pathologic changes within a lobule and may be helpful in the differential diagnosis of diffuse pulmonary diseases.
TL;DR: Balloon-expandable intraluminal grafts that ranged in diameter from 2 to 4 mm were placed in the atherosclerotic abdominal aortas of 24 rabbits and retained patency without altering the luminal diameter.
Abstract: Balloon-expandable intraluminal grafts that ranged in diameter from 2 to 4 mm were placed in the atherosclerotic abdominal aortas of 24 rabbits. The animals were killed 1, 3, 8, or 24 weeks after placement of the graft. All grafts retained patency without altering the luminal diameter. The small degree of neointimal thickening covering the graft's inner surface was not detectable on conventional in vivo arteriograms. Aortic atherosclerotic plaque external to the graft was markedly compressed 1 week after graft placement. The plaque regained full thickness 24 weeks after grafting when the plaque expanded outside the graft as a result of relaxation or atrophy of the surrounding arterial media.